This invention relates to gasoline compositions containing additives for improving the octane rating of said gasoline, and more specifically to gasoline compositions containing stabilizers for said additives.
MCMT is presently being used as a component of gasoline fuels to improve the octane number thereof. However, in the proportions in which it is present in the gasoline fuels, usually between about 0.05 and 0.20 gm/gal (as manganese), MCMT is unstable. In the presence of sunlight, or other source of ultra-violet radiation, MCMT rapidly oxidizes to components that precipitate, with the rate of oxidation being dependent upon the concentration of dissolved oxygen in the gasoline. Thus, when gasoline containing 0.1 gm/gal MCMT (as manganese) is exposed to sunlight, within about 2-3 hours nearly complete oxidation of MCMT occurs, and a precipitate of oxidation products is formed. Similar oxidation takes place in the absence of sunlight, but at a somewhat slower rate. Cnsequently, gasoline compositions containing MCMT which are placed in storage for even few weeks suffer a significant decrease in octane rating and form a solid precipitate capable of clogging valves, transfer lines, etc.